Propeller or turbine for water, air, and gases



May 10, 1932. A. HoLMsTRoM PROPELLER OR TURBINE FOR WATER, AIR, AND GASES 5 Sheets-Sheet l Filed April 8. 1929 mw w /f w wv nllflnllall- Illlllill- MN w MH www ,//f J k 2x 0 x.

' May' l0, 1932.v A. HoLMsTRoM PROPELLER OR TURBINE FOR WATER, AIR, AND GASES 5 Sheets-Sheet 2 Filed April 8, 1929 May 1o, 1932. A, HOLM'STOM 1,857,509

PROPELLER OR TURBINE FOR WATER, AIR, AND GASES` Filed April 8, 19,29` 5 sheets-sheet 3 Patented May I0, 1932 V N A',UNrra-D ASTA AXEL-HOLMSTROM; F MONTE oARLopMoNaco';

, PROPELLEB 0R TURBINE Fon wATnaArRQANDGAsEs; i i Y Appneatiqn mea April s, 1929, serial No. 353,407, and in Germany otober `172, 192s.

My invention relates to water craft, -air craft Vor the like and to a propeller therefon.

One purpose of my invention is' to provide a propeller ofthe type indicated "with a vstream-line core along its axis in order to give the uid, operated upon by the propeller stream-"line approach into 'the propeller and stream-line rearward delivery away'from the propeller.

A further purpose is to decrease the blade friction; of a; propellerl by giving the blade a fish-scale surface, preferably delivering'air through the propeller to the scale edges.

. Afurthery purpose is to Ylessen-thev friction f of a water craft bygi'ving its submerged portion afish-scale surfaceI nd'by discharging air tothe edges v.of the scales.`

A further purpose is toguide thelliuidV discharge of a propeller inwardlytoward the propeller axis along streamlines by means of a tubular guide around thel outside of theA propeller, preferablyk placing a 'cooperating "guide as astreamline core in the propeller axis extending rearwardly from the propeller, the `outer tubular guide providing- Vstreamline inwardflow to the core.

Further purposes will appearin the speciication and in the claims. Y Figure l is a fragmentary View showing a propeller fora motor boat or the like, said propeller embodying a desirable form of one feature of my invention.

n Figurev 2 is` a perspective view to considerable' extent diagrammatic indicating a somewhat dilferent formv of propeller from thatof Figure l. Y

Figure 3 is a fragmentary endelevation of a desirable form o f propeller embodying some features of myinvention.V

, Figures 4,45 and 6, arepsections of `different'` desirable streamline forms for the propeller vlolade,veach form presenting a Vfish-scalesurface to the reacting fluid.'A

' `Figure 7 'sa fragmentary horizontal view water surface showing a desirable sh scale structure lupon the outsidefofthe submerged surface of a boat.

`through the side wall. of ai boat beneath .the

Itis evfdent that the reaction of the expansionxof thecompressed mediumon suchrl bodies will be'grea'ter, yth(- .higlie rthe com-" pression isand the'more it can bel concentrat-v` "ed, V The compressed medium would,'so` to sp ak,'act` as anaccumulator and lpress'the bodyforward. like agpiston.

This invention relates to` a stream-linebodyww Y on whichl specially formed propellery blades are arranged in suchpaway as `tofshovel or draw the'mediumbfrom ahead, pressi't t'ogether and drive it towards the rear partof, the body in the form of a compressed medium A"nii column. Irle'reby'also the center part ofthe lmediumQfor instance water,"1will. be utilized and notV only, as heretofore, the outer partof the vmedium column. Thus all of the medium within reach of the propeller action, also the'j-SO center part of the mediumcolumnywillbe taken in by the propeller blades andfdriven rearwards as a compressed medium' column. 1 The'effect of the propeller canbe still furthenm increased through afspecial construction of` the surface of the ypropeller bladesl 'Itis -well k'nown that 'the' scales 'of a; fish j tend to reducethe frictioninwater, because of the veryl'ow adhesion of water to the, scales, and therefore of the fish. A

Furtherriiorel the smooth scales'overlapj each 'othen giving the'.v surface'a steplike formation. VfBy motion forward an air-filled space isformed back of each oflthese,` stepsf'95- jwhi'ch tends to `reduce the resistance'of the fish at thesame time, as the 'pressure of the medium-column ony the rear" part of the'body w is taken up by these steps:"' i

These facts are utilized in the newfpro- 10"' facilitatethe swimming'bo f i peller by giving the surfacesof the propeller body and propeller blades a step formation and a series of openings through which air can be released.

The propeller body a has a streamline formation, the front part of the body, seen from the side, 4showing elliptical` lines at b which Arun together to a poi-nt cf. Rearwardly at l the lines run slowly together, giving the rear partV of the body a pyramidal vor conical or preferably vconoidal formwith sufficient surface to take up the pressure of the Water the-conveXity-of longitudinal sections throughpthe axis is quite desirable to secure the stream line eec't sought.v The `front .partpf the body carries .the .propeller .blades which serve a ,double purpose.

Theblades, when revolving, notonly drive i the.body .fforward butalso at ,the ysame time draw7 the water to the propeller, press Ait `b ev.tween.the.blades and vdrive it backwards,

draw the water .to the propeller aswell from the @Xtremetends ofthe bladeszas from the .center ofthe medium column, as shown byE lthe streamlinesyand .rearwardly rof the :blade jrpress .it inward. against the propeller .body d.

,.Thnsithe waterlis draw-nin. .bygthe pro- .fllhisrwater,.column, on its way from the Y front part ,of the stream-line `bodvto the widest section .of .the same, is naturally being Y.more.and more compressed, until after pass- ..4 0'

ing .this section it aga-in .expands and reacting on therearward sloping part Vd of the body,

.pressesthe body evenly and forcefully foruward with apressure proportionate to the 5....fexpansion. The rings f preventy expansion.

V-to:.determine .the.direction.fof ,rearward flow .outwardly .oppositeflthe propellers and help v.ofthe column.

Trials .have shown that higher speeds than .heretofore ,possible canbe obtained with a propeller ofthis type.

To further. improvethe -action of the pro peller, :its blades are lgiven. scale-formed surfaces, as-shown in Figures 3 to 9. ,Thesur-.

. faces arenotsmooth but provided withsteps small openings on the side.

.Eigures :3 ,to 9` show al few of the many ,differentlforms .of such steps-or scales; This arrangement-not only prevents the medium,

for instance. water, from sticking to the revolving blades because ofthe continuous inmesh .with rthe Vgear15. {'Ilorrprevent expansion of the compressed.V medium .awayfrom :the :center V.of the y .pro-V mpeller, .girdle-rings fare arranged.

When ,the propeller revolves, its .blades friction.

h of suitablefformation, these steps having,

kforwardportion .'oflthe core Z), a gear 15 fastened to the core'member and a tubular shaft-'16, 'allof `these'elements turning as a unit.l y.

y The rotor shaft 16 is rigidly fastened in the :hollow forwardportionof thecore and is 4 mounted .in bearings ,and1'8j inside .the hollow .rearward portion-d ,of the corefwhich also gives a `rb earing.- support' .tol-'the lower ,end .of ,a `drive shaft; 19 `carryingia gear 20.1.11

e The .drive shaft-..19 is insidea hollowwertticalkarm .21, which extends .downwardfrom the bottoml of the craft carrying the propeller,forexample from the bottom of amotorf bOat, l the `shaft beingdriv'en by .a motQI- nside they craft,fgnothshown, :being irrelevant to the presentinvention".Y

-The Vvertical 21 .'s

desirably angularly movablebnits .own axis. foradaptationto v5;

use. as "a, rudder, .the rearward end .O the core then being provided withllsQQ alining with the .current discharging frorntheg propeller. `In Figure f2, the zcore,.sl 1 aft ,andthe propeller blades areasingle member rotatingasgfi `aunit. ,r n ,Y -`The shaft 1 6? projects rearwardlyv or, forwardly throughthe end .off the craft,-:f,or

example through the stern or bow of ,a motor bo at, in.to thewatenzand the girdle ringff;

surrounding the 4.blades Amay. either fbe sepa ratelysupported from the craft ormay rotate with the blades, ',.accordi'ng .to preference vor circumstance. i

As indicated nFgures .Btc 6 thesurface .of the propeller vis preferably provided With' fishlscale steps andprfelably air is delivered to `the surface ofthe propellerat the edgesof the steps anysuitable,way, both the step yformation.and.,the introductionfofpr air at the step edges'reducin'gthefpropeller InFigure 1 lthe@ airy may. be delivered throughthe hollowffshafts 19 .and 16 and intermediate perforationsQ and 24:,into the 5 hollow core member @b andthencethrough perforations 27 intoiftle interiory .Of the' i'n- 'Y dividual propeller4 blades, to escape, at the ,edges of the fishs'c-ale steps at the openings.

Figures Sto Gare to, a consideralble'extentz` `diagrammiati-c and illustrate a ffew Vonly' of the many different forms the propeller blades may take, thesef views correspondingtosections yperpen dicular `to radiiat Vthe; n 1`i(il d le of` f -th respective blades; thsdireceaejefleeres ment of the blade corresponding to that indicated by the arrows.

Figures 7 to 9 illustrate another desirable feature of my invention, that is lparticularly advantageous when applied to the submerged surface of a motorboat.

I provide the outside submerged portion of a boat with what I have called a fish-scale surface in which the outer plates 7L fastened to the outside of the boat at le form a succession of steps similar to those of a shingle roof or to those presented by the .scales of a fish.

VThe movement of the boat is in the direction of the arrows so that the fluid through which the boat is moving passes successively over the steps. Preferably air is delivered to the edges of the steps either from' the interior of the boat into suitable compartments e and thence out through openings z' or from the outside of the boat. V

It will be understood that a speeding motorboat may skim the water surface in a. way

' that causes a stream of air to pass under the boat. This air fills the spaces at the edges of the steps of the fish-scale surface and results in a lessened friction between the water and the bottom of the boat.

It will be noted that the body of my propeller is generally pear-shaped.` The forward portion is preferably elliptical and the rearward portion preferably conveXly conoidal.. 1

In view of my invention and disclosurev variations and modiiications'to meet individual whim' or particular needwill doubtless become evident to others skilled in the art, to obtain all or part of the benefits of my invention without copying the structure shown, and I, therefore, claim all such in so far as they fall within the reasonable spirit and scope of my invention.

Having thus described my invention, what` I claim as new and desire to secure by Let-V the outside ofA travel of the body and connections for delivering air through the bodyV to release it at the surface adjacent the edgesof the steps.

5. A propeller including a stream-line core at the 4propeller axis, means for rotating the front part of the core as a part of the 'prop-eller, means for rearwardly supporting the rear part of the core in line with the rotatj able core part, a succession of fish-scale steps on the working face of the propeller, said step surfaces facing rearwardly with respect' to the direction of their circumferential travel to permit the fluid operated upon by the Yim- C peller to slide more easily past the steps and means for delivering air to the working faces.

of the impeller alongthe step faces.

6. In a propeller, blades having circumferentiallyV rearwardly directed steps on the workin surface hollow propeller Y thereof and openings at the step y acesinto the hollow interiorand a hollow propeller shaft in conduit connectionwith the hollow of the blades and with a source of air supply for releasing Vair at the 'step surfaces;`

7.' In a propeller for use in water, a bearing having a fixed support, a hollow shaft mount- Y ed'in the bearing, a gear thereon, a second,

'gear meshingwithV the first, a hollow shaft for thesecond gear, asecondbearing having a supporting connection with the first bearing and hollow propeller blades supported by the second hollow shaft whereby air admitted undery pressure into the first hollow shaft may be released at the surfaces of the blades.V AXEL HOLMSTROM.

surface without engaging the abutment faces r Vthereof and means for delivering and liberating air on the said surface at the edges' of the scales.

3. A craft for travelling through fluid, said .I

rected `rearwardly of the line of travel and l 

